I ran into a freebie.....complete Parker X,Y,Z slides,stepper motors and drivers package a few month back. The travels are 18"x18"x 12. The plan is to have 1/2" subplate under the table slide as the base to bolt the uprights for the gantry. The gantry was built extra tall to allow for shifting the 3/4" subplate mounted Y-axis slide up 4" to get more Z occasionally. Most of the time the Z will only travel 8" to keep things rigid. I may key the Y subplate to the uprights along with dado the rear brace as well. My fear is a weak point where the uprights bolt to the table subplate. I was thinking of adding strong back supports to the outsides of the uprights, but thought that might be overkill.


I figured I would post this up here and see if anyone can tell me if the strength in 3/4" aluminum plate on this stationary router design would present any hidden problems I may have missed. I have seen some of the box gantry designs in MDF, so this is somewhere one step above them in material strength only. As long as it doesn't ring like a bell under cutter chatter. The materials cut could be from pink insulating foam to brass.

I have the newest CNC4PC multi-board. Maybe those that have had success with using laptops could post the specs of what laptops could be used with the CNC4PC + Mach3 combination. Rather than being tide to a desk top machine.

For the most part, I just need to make the structure and assemble it. The circuit should be a simple. The software interface is another area I may be back for help on. Thanks for scoping it out!

DC

Looks good. I would be cautions of that much z travel and height. Most router bits are only good for 1-2" of cut. If you are using 3/4" aluminum plate for the uprights, I would think that is plenty strong, and it would not be difficult to reinforce later if need be.

Btw, I also got a good deal on an xy stage. No motors though. I am reconfiguring it to have 12"x12"x3" capacity. Going to use servos on mine.

Can't comment on the cnc4pc and laptop usage. I have the cnc4pc with a desktop and have no issues using EMC2.

I have it drawn with the Z axis centered on the lower 8" of travel while the Y axis slide is in the lower position. If I needed to mount a part on a 4th axis(In the distant future), I wanted a bit more room under the Y axis slide. So I designed it to be 2 position adjustable and dowel pinned for each location.

I wouldn't want to cut anything while the Z extended down full 12". As it is, I'm worried about the Spindle mount resulting overhang off the Z slide block. Although that is 1" thick aluminum plate, the length from the cutter tip to the sliding block is 13". The cutter as drawn was only for a 4" reference from the table to the collet.

I've started cutting up some 3/4" plate for the uprights.

Thanks for the reply.

DC

What if you reversed the Z axis assembly such that the rods move and the bearings mount to the bearings on the gantry. That might let you shorten the distance from bearing to tool and perhaps loose a little weight.

Where can I get some of those "freebies" :)

Steve

Hi Steve,

Good eye!

Yes, I had looked at that option too. About the only decision against it was that the whole Z axis slide assembly would move up and down. The added strength may be of more benefit although I would need to include a cable flex track.

I'll redraw that portion to get a better idea of how it turns out. The traveling carriage block for the Z is 6"x6" with 5/8"x18" rails mounted on aluminum extrusions.

It certainly does shorten up the overhang by 8". I had considered adding some linear rails to the back of that spindle sub-plate and linear bearings to the lower portion of the slide. I'd lose some travel and gain weight, so that didn't make it too far.

Freebies come form a close friend that owns a scrap yard....which can turn you into a packrat in a hurry. I have learned to at least minimize things from following me home that I can use immediatley. Otherwise I was storing it for a while, then taking it back to the yard. For now, I just get a kick out of tearing things apart to see how they work and throwing it back it the pile.:p

DC